Help with my java GUI

Hey guys I know it’s been a while but in my defense I have been reading on GUI and I have hit a bump on the road can anyone help me.

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import javax.swing.JOptionPane;

public class Program
{
public static void main(String[] args) {
String fn = JOptionPane .showInputDialog(“Enter first number”);
String sn = JOptionPane .showInputDialog(“Enter second number”);

int num1 = Integer.parseInt(fn);
int num2 = Integer.parseInt(sn);
int sum =num1 + num2;

JOptionpane.showMessageDialog(null, "The sum is " +sum, "calc", JOptionpane.PLAIN_MESSAGE);

}

}
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